Currently, the conventional five-compressing-chamber diaphragm pumps exclusively used with RO (Reverse Osmosis) purifier or RO water purification system, which is popularly installed on the water supplying apparatus in either the settled home, recreational vehicle or mobile home, have some various types. For five-compressing-chamber diaphragm pumps, other than the specific type as disclosed in the U.S. Pat. No. 8,449,267, the majority of conventional five-compressing-chamber diaphragm pumps can be categorized as similar design as shown in FIGS. 1 through 10. The conventional five-compressing-chamber diaphragm pump aforesaid essentially comprises a motor 10 with an output shaft 11, a motor upper chassis 30, a wobble plate with integral protruding cam-lobed shaft 40, an eccentric roundel mount 50, a pump head body 60, a diaphragm membrane 70, five pumping pistons 80, a piston valvular assembly 90 and a pump head cover 20, wherein said motor upper chassis 30 includes a bearing 31 to be run through by the output shaft 11 of the motor 10, an upper annular rib ring 32 with several fastening bores 33 disposed therein in circumferential rim evenly; said wobble plate with integral protruding cam-lobed shaft 40 includes a shaft coupling hole 41 for being run through by the corresponding motor output shaft 11 of the motor 10; said eccentric roundel mount 50 includes a central bearing 51 at the bottom thereof for corresponding wobble plate with integral protruding cam-lobed shaft 40, five tubular eccentric roundels 52 disposed thereon in circumferential location evenly such that each tubular eccentric roundel 52 has a horizontal top face 53, a female-threaded bore 54 and an annular positioning dent 55 formed on the top face thereof respectively in horizontal flush, as well as a rounded shoulder 57 created at the joint of the horizontal top face 53 and a vertical flank 56; said pump head body 60, which covers on the upper annular rib ring 32 of the motor upper chassis 30 to encompass the wobble plate with integral protruding cam-lobed shaft 40 and eccentric roundel mount 50 therein, includes five operating holes 61 disposed therein in circumferential location evenly such that each operating hole 61 has inner diameter slightly bigger than outer diameter of the tubular eccentric roundel 52 in the eccentric roundel mount 50 for receiving each corresponding tubular eccentric roundel 52 respectively, a lower annular flange 62 formed thereunder for mating with corresponding upper annular rib ring 32 of the motor upper chassis 30, several fastening bores 63 disposed thereat in circumferential location evenly; said diaphragm membrane 70, which is extrude-molded by semi-rigid elastic material and to be placed on the pump head body 60, includes a pair of parallel outer raised brim 71 and inner raised brim 72 as well as five evenly spaced radial raised partition ribs 73 such that each end of radial raised partition rib 73 connects with the inner raised brim 72, five equivalent piston acting zones 74 are formed and partitioned by the radial raised partition ribs 73, wherein each piston acting zone 74 has an acting zone hole 75 created therein in correspondence with each female-threaded bore 54 in the tubular eccentric roundel 52 of the eccentric roundel mount 50 respectively, and an annular positioning protrusion 76 for each acting zone hole 75 is formed at the bottom side of the diaphragm membrane 70 (as shown in FIGS. 8 and 9); each said pumping piston 80, which is respectively disposed in each corresponding piston acting zones 74 of the diaphragm membrane 70, has a tiered hole 81 run through thereof, after having each annular positioning protrusion 76 in the diaphragm membrane 70 inserted into each corresponding annular positioning dent 55 in the tubular eccentric roundel 52 of the eccentric roundel mount 50, by running fastening screw 1 through the tiered hole 81 of each pumping piston 80 and the acting zone hole 75 of each corresponding piston acting zone 74 in the diaphragm membrane 70, the diaphragm membrane 70 and five pumping pistons 80 can be securely screwed into each female-threaded bore 54 of corresponding five tubular eccentric roundels 52 in the eccentric roundel mount 50 (as enlarged view shown in FIG. 10 of association); said piston valvular assembly 90, which suitably covers on the diaphragm membrane 70, includes a downward outlet raised brim 91 to insert between the outer raised brim 71 and inner raised brim 72 in the diaphragm membrane 70, a central dish-shaped round outlet mount 92 having a central positioning bore 93 with five equivalent sectors each of which contains multiple evenly circum-located outlet ports 95, a T-shaped plastic anti-backflow valve 94 with a central positioning shank, and five circumjacent inlet mounts 96, each of which includes multiple evenly circum-located inlet ports 97 and a inverted central piston disk 98 respectively so that each piston disk 98 serves as a valve for each corresponding group of multiple inlet ports 97, wherein the central positioning shank of the plastic anti-backflow valve 94 mates with the central positioning bore 93 of the central outlet mount 92 such that multiple outlet ports 95 in the central round outlet mount 92 are communicable with five inlet mounts 96, and a hermetical preliminary-compressing chamber 26 is formed between each inlet mount 96 and corresponding piston acting zone 74 in the diaphragm membrane 70 upon the downward outlet raised brim 91 having inserted between the outer raised brim 71 and inner raised brim 72 in the diaphragm membrane 70 such that one end of each preliminary-compressing chamber 26 is communicable with each corresponding inlet ports 97 (as enlarged view shown in FIG. 10 of association); and said pump head cover 20, which covers on the pump head body 60 to encompass the piston valvular assembly 90, pumping piston 80 and diaphragm membrane 70 therein, includes a water inlet orifice 21, a water outlet orifice 22, and several fastening bores 23 while a tiered rim 24 and an annular rib ring 25 are disposed in the bottom inside of said pump head cover 20 such that the outer brim for the assembly of diaphragm membrane 70 and piston valvular assembly 90 can hermetically attach on the tiered rim 24 (as enlarged view shown in FIG. 10 of association), wherein a high-compressing chamber 27 is configured between cavity formed by the inside wall of the annular rib ring 25 and the central outlet mount 92 of the piston valvular assembly 90 upon having the bottom of the annular rib ring 25 closely covered on the brim of the central outlet mount 92 (as shown in FIG. 10).
By running each fastening bolt 2 through the each corresponding fastening bores 23 of pump head cover 20 and each corresponding fastening bore 63 in the pump head body 60, then putting a nut 3 onto each fastening bolt 2 to securely screw the pump head cover 20 and pump head body 60 with the motor upper chassis 30 via each corresponding fastening bore 33 in the motor upper chassis 30 so that the whole assembly of the five-compressing-chamber diaphragm pump is finished (as shown in FIGS. 1 and 10).
Please refer to FIGS. 11 and 12, which are illustrative figures for the operation of “conventional five-compressing-chamber diaphragm pump”.
Firstly, when the motor 10 is powered on, the wobble plate 40 is driven to rotate by the motor output shaft 11 so that five tubular eccentric roundels 52 on the eccentric roundel mount 50 orderly move in up-and-down reciprocal stroke constantly;
Secondly, meanwhile, five pumping pistons 80 and five piston acting zones 74 in the diaphragm membrane 70 are orderly driven by the up-and-down reciprocal stroke of five tubular eccentric roundels 52 to move in up-and-down displacement;
Thirdly, when the tubular eccentric roundel 52 moves in “down stroke” with pumping piston 80 and piston acting zone 74 in down displacement, the piston disk 98 in the piston valvular assembly 90 is pushed into “open” status so that the tap water W can flow into the preliminary-compressing chamber 26 orderly via water inlet orifice 21 in the pump head cover 20 and inlet ports 97 in the piston valvular assembly 90 (as shown in FIG. 11 and arrowhead indication W in enlarged view of association);
Fourthly, when the tubular eccentric roundel 52 moves in “up stroke” with pumping piston 80 and piston acting zone 74 in up displacement, the piston disk 96 in the piston valvular assembly 90 is pulled into “close” status to compress the tap water W in the preliminary-compressing chamber 26 to increase the water pressure therein up to range of 100 psi-150 psi and become into pressurized water Wp with result that the plastic anti-backflow valve 94 in the piston valvular assembly 90 is pushed to “open” status;
Fifthly, when the plastic anti-backflow valve 94 in the piston valvular assembly 90 is pushed to “open” status, the pressurized water Wp in the preliminary-compressing chamber 26 is directed into high-compressing chamber 27 via group of outlet ports 95 for the corresponding sector in central outlet mount 92, then expelled out of the water outlet orifice 22 in the pump head cover 20 (as shown in FIG. 12 and arrowhead indication Wp in enlarged view of association); and
Finally, with orderly iterative action for each group of outlet ports 95 for five sectors in central outlet mount 92, the pressurized water Wp is constantly discharged out of the conventional five-compressing-chamber diaphragm pump for being further RO-filtered by the RO-cartridge so that the final filtered pressurized water Wp can be used in the RO (Reverse Osmosis) purifier or RO water purification system, which is popularly installed on the water supplying apparatus in either the settled home, recreational vehicle or mobile home.
Referring to FIGS. 13 and 14, a primary serious drawback has long-lasting existed in the foregoing “conventional five-compressing-chamber diaphragm pump” as below. As described previously, when the motor 10 is powered on, the wobble plate 40 is driven to rotate by the motor output shaft 11 so that five tubular eccentric roundels 52 on the eccentric roundel mount 50 orderly move in up-and-down reciprocal stroke constantly, and five piston acting zones 74 in the diaphragm membrane 70 are orderly driven by the up-and-down reciprocal stroke of five tubular eccentric roundels 52 to move in up-and-down displacement so that equivalently a reiterative acting force F constantly acting on the bottom side of each said piston acting zone 74.
Meanwhile a plurality of rebounding force Fs is created to react the acting force F exerting on the bottom side of diaphragm membrane 70 with different components distributed over entire bottom area of each corresponding piston acting zone 74 in the diaphragm membrane 70 (as shown in FIG. 14) so that a “squeezing phenomenon” happens on the partial portion of the diaphragm membrane 70, which is incurred by the rebounding force Fs.
Among all distributed components of the rebounding force Fs, the component force happened at the contacting bottom position P of the diaphragm membrane 70 with the rounded shoulder 57 of the horizontal top face 53 in the tubular eccentric roundel 52 is maximum so that the “squeezing phenomenon” happened here is also maximum (as shown in FIG. 14).
With rotational speed for the motor output shaft 11 of the motor 10 reaching a range of 800-1200 rpm, each bottom position P at the piston acting zone 74 of the diaphragm membrane 70 is suffered from the “squeezing phenomenon” in a frequency of five times per second. Under such circumstance, the bottom position P of the diaphragm membrane 70 is always the first broken place for entire conventional five-compressing-chamber diaphragm pump, which is the essential cause for not only shortening the service lifespan but also terminating normal function of the conventional five-compressing-chamber diaphragm pump.
Therefore, how to substantially reduce all the drawbacks associated with the “squeezing phenomenon” caused by the reiterative acting force F constantly acting on the bottom side of each said piston acting zone 74 of the diaphragm membrane 70, which is incurred by the tubular eccentric roundel 52, for the conventional five-compressing-chamber diaphragm pump becomes an urgent and critical issue.